In the early years of the reign of Frederick the Great, Münchow was not only a soldier and a diplomatic confidant, but he also earned a reputation for the improvement of Prussian military medical care.

The father was a master of Kosemühl, a royal Brandenburg cornet at a young age, and when Crown Prince Frederick was imprisoned between 1732–1733, he was chamber president in Küstrin.

During the Spanish War of Succession, he fought in the Prussian contingent on the imperial side in the battles of Malplaquet and Ramillies.

[2] In the course of the First Silesian War, in May 1741, Münchow took over the supervision of the Prussian hospitals set up in the neutral Wroclaw after the Battle of Mollwitz.

Münchow's most important improvement was the separate treatment and care of the sick from wounded, which greatly reduced the danger of cross infection.

[2] For his success, in July 1742, Frederick awarded Münchow the Order Pour le Mérite and appointed him in September 1742 to major general.

There, on the left wing of the first meeting with the regiments Borcke, Blankensee and Bevern, he held the position until the attack of the Bayreuth Dragoons decided the battle in favor of Prussia.

Frederick II, in the first year of his reign in October 1740, endowed Münchow with a place as a canon at the cathedral at Magdeburg, and he later became Chancellor of the Order.